Alert archive / Iowa / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 119, NWS Quad Cities, IA

July 20, 20195 counties in Iowa

NWS Quad Cities, IA issued this severe thunderstorm warning at Jul 20, 2019, 7:37 PM CDT for 5 counties in Iowa. It was in force for 39 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 20, 2019, 7:37 PM CDT (00:37 UTC)
Expired
Jul 20, 2019, 8:16 PM CDT
In force
39 min
Issued by
NWS Quad Cities, IA
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Henry County, IA, Jefferson County, IA, Keokuk County, IA, Van Buren County, IA, Washington County, IA

The radar

The Quad Cities radar (KDVN), 122 km from the middle of the area, began a volume at 00:37 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jul 20, 4:58 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 00:00Z, 0.6 hours before the alert went out and 295 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Lincoln, IL at 00:00Z on 2019-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1779 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lincoln, IL at 00:00Z on 2019-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 31 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1779 J/kg
Mixed-layer CIN
-108 J/kg
Mixed-layer LCL
1507 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
31 m²/s²
0-3 km storm-relative helicity
68 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Quad Cities, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 20, 7:10 PM CDT, 27 minutes earlier.

Area forecast discussion, Jul 20, 7:10 PM CDT, 27 minutes before
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Hazardous weather outlook, Jul 20, 12:17 PM CDT, 7 hours 20 minutes before
Hazardous Weather Outlook
National Weather Service Quad Cities IA IL
1217 PM CDT Sat Jul 20 2019

IAZ040>042-051>054-063>068-076>078-087>089-098-099-ILZ001-002-007-
009-015>018-024>026-034-035-MOZ009-010-211730-
Buchanan-Delaware-Dubuque-Benton-Linn-Jones-Jackson-Iowa-Johnson-
Cedar-Clinton-Muscatine-Scott-Keokuk-Washington-Louisa-Jefferson-
Henry IA-Des Moines-Van Buren-Lee-Jo Daviess-Stephenson-Carroll-
Whiteside-Rock Island-Henry IL-Bureau-Putnam-Mercer-Henderson-
Warren-Hancock-McDonough-Scotland-Clark-
1217 PM CDT Sat Jul 20 2019

This Hazardous Weather Outlook is for portions of north central
Illinois...northwest Illinois...west central Illinois...east
central Iowa...northeast Iowa...southeast Iowa and northeast
Missouri.

.DAY ONE...THIS AFTERNOON AND TONIGHT

An Excessive Heat Warning remains in effect for the entire outlook
area until 7 PM this evening. Very high heat indices between 100
and 110 degrees are expected.

A cold front will move slowly across the area tonight with
numerous thunderstorms expected to develop along and behind the
front. There is an enhanced risk for severe storms and damaging
winds of at least 70 mph north of a Freeport to Dubuque to
Edgewood line. There is also a risk for isolated tornadoes.

There is a slight risk of severe thunderstorms across much of the
remainder of the area. The main threats will be large hail and
damaging winds. Additionally, thunderstorms will produce heavy
rainfall and may also hit the same area repeatedly overnight which
may cause flash flooding.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

Thunderstorms are likely on Sunday as a cold front continues to
move slowly south through the area. Severe thunderstorms are
possible, mainly for areas south of Interstate 80, with damaging
winds, heavy rain and flash flooding being the primary threats.
There is a marginal risk for severe storms.

.SPOTTER INFORMATION STATEMENT...

Spotter and amateur radio network activation may be needed
especially this evening and overnight.

Haase

In the hours before

Special weather statement, Jul 20, 2:08 PM CDT, 5 hours 29 minutes before
Special Weather Statement
National Weather Service Quad Cities IA/IL
208 PM CDT Sat Jul 20 2019

ILC015-085-177-IAC045-061-097-105-113-202000-
Jo Daviess-Carroll-Stephenson-Jackson-Dubuque-Jones-Linn-Clinton-
208 PM CDT Sat Jul 20 2019

...A LINE OF THUNDERSTORMS AND STRONG WIND GUSTS WILL AFFECT JO
DAVIESS...NORTHWESTERN CARROLL... NORTHWESTERN
STEPHENSON...JACKSON...SOUTHERN DUBUQUE...JONES...EAST CENTRAL LINN
AND NORTHWESTERN CLINTON COUNTIES UNTIL 300 PM CDT...

At 206 PM CDT, Doppler radar indicated developing thunderstorms with
strong wind gusts were located along a line extending from near
Menominee to near Langworthy. Movement was east at 45 mph.

Winds in excess of 40 mph are possible with these showers, with wind
gusts near 50 mph possible in thunderstorms.

Locations impacted include...
Dubuque, Maquoketa, Anamosa, Galena, Marion, Asbury, Monticello,
Savanna, Lena, Bellevue, Cascade, Stockton, East Dubuque, Warren,
Peosta, Springville, Preston, Hanover, Elizabeth and Woodbine.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional
information and possible warnings from the National Weather Service.

LAT...LON 4251 9064 4249 8952 4202 9021 4204 9163
      4256 9066
TIME...MOT...LOC 1906Z 276DEG 40KT 4254 9057 4219 9130

Speck
Local storm report, Jul 20, 2:23 PM CDT, 5 hours 14 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
223 PM CDT SAT JUL 20 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0150 PM     TSTM WND DMG     2 NE DUBUQUE            42.52N 90.66W
07/20/2019                   DUBUQUE            IA   TRAINED SPOTTER

            SEVERAL 1-2 INCH TREE BRANCHES DOWN NEAR
            RESIDENCE, ONE 4 FOOT LONG 2 INCH HEALTHY
            TREE BRANCH DOWN. ALSO NOTED SOME SHINGLES
            BLOWN DOWN ON SHED. TIME ESTIMATED FROM
            RADAR.

&&

GROSS
Local storm report, Jul 20, 2:58 PM CDT, 4 hours 39 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
258 PM CDT SAT JUL 20 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0250 PM     FUNNEL CLOUD     1 N LOWDEN              41.90N 90.93W
07/20/2019                   CEDAR              IA   CO-OP OBSERVER

            WENT DOWN HALF WAY AND NOW IS GOING BACK UP.
            ALSO REPORTED VIA LAW ENFORCEMENT.

&&

GROSS
Special weather statement, Jul 20, 3:38 PM CDT, 3 hours 59 minutes before
Special Weather Statement
National Weather Service Quad Cities IA/IL
338 PM CDT Sat Jul 20 2019

ILC015-177-202115-
Carroll-Stephenson-
338 PM CDT Sat Jul 20 2019

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT NORTHEASTERN CARROLL
AND STEPHENSON COUNTIES UNTIL 415 PM CDT...

At 338 PM CDT, radar indicated strong thunderstorms were located
along a line extending from Pecatonica to near Forreston to near
Chadwick. Movement was east at 35 mph.

Wind gusts up to 50 mph are possible with these storms.

Locations impacted include...
Freeport, Mount Carroll, Lanark, Pearl City, Shannon, Cedarville,
Davis, Dakota, German Valley, Rock City, Ridott, Rock Grove, Hitt,
Afolkey, Scioto Mills, Winneshiek, Dakota Dornink Airport, Albertus
Airport, Bolton and Stephenson  County Fairgrounds.

Torrential rainfall is also occurring with these storms. Minor
flooding of low lying areas, creeks, streams and urban areas is
possible. If you encounter water over a roadway, do not drive through
it.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

LAT...LON 4220 8940 4220 8969 4196 8969 4209 9000
      4229 8981 4250 8952 4250 8940
TIME...MOT...LOC 2038Z 264DEG 29KT 4233 8934 4219 8960 4205 8988

Gibbs

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 20, 7:55 PM CDTSpecial Weather StatementDVNLee, Van Buren65 min
Jul 20, 8:17 PM CDTSpecial Weather StatementDVNHenry58 min
Jul 20, 8:45 PM CDTSpecial Weather StatementDVNLee60 min

Nearby

Severe Thunderstorm Warnings in Iowa, 2019Every severe thunderstorm warning in 2019

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.